The present invention relates to a surgical retractor blade used in conjunction with a table fixed retractor system and more particularly is directed to a surgical retractor blade that is particularly advantageous for use in orthopaedic surgery.
In various surgical operations, it is customary to employ surgical retractors. Many such retractors are held in position over the operative site by some type of frame work that is affixed to the operating room table. Some retractor systems employ retractor rings that are positioned over the operative site and the actual retractor blade assemblies are attached to this ring when in use. The retractor blade is applied to the tissue to move it into the desired position and the blade is locked onto the retractor ring so that it is self retained in the proper position during the surgical procedure. These retractors, are generally known as table-fixed surgical retractors. Although the retractor rings find greatest use in abdomen and head surgery, they can also be used in other surgical procedures. Typical variations of this type of retractor are found in U.S. Pat. Nos. 4,934,352; 3,572,326; 2,594,086 and 2,586,488.
The retractor blades themselves have generally flat surfaces which are rigidly affixed to a rod or a bar which in turn is affixed to the retractor ring. To obtain the desired degree of retraction, pressure is exerted on the rod to force the tissue away from the point of the incision and then the rod is secured to the retractor ring. The pressure exerted on the tissue is the force of the blade being held onto the ring. The flat portion of the blade exerts pressure on the tissue to hold it in the desired position out of the operative site and to fully expose the operative site.
The force necessary to move the tissue to expose the operative site with a standard retractor is applied solely by pulling the blade toward the ring or tilting the blade down with a ratchet mechanism which connects the rod to the fixed ring. A ratchet mechanism of this type is disclosed in U.S. Pat. No. 4,424,724. In certain surgical procedures particularly orthopaedic procedures, it is difficult to supply the desired force by pulling the blade in one direction.